I gave Isis, Between the Buried and Me, and High on Fire a listen, and I found them too metal for my tastes. Too much thrash, not enough melody imho.
I thought Meshuggah had a similar issue, and King Crimson didn't really resound with me.
Porcupine tree and Russian Circles I thought were quite cool. <--- More like this! =)
Ashes Divide's new album Just Keep Telling Myself It's Alright I thought was great, it's a lot more mellow than say, Tool or APC, which maybe is why I liked it to much.
Thanks for all the suggestions, so far I've found very much to my liking:
Baroness
Cog
Karnivool
Pocupine Tree
Russian Circles
Dredg
I think that I don't like Tool for its metal qualities, but rather for its melodic and progressive rock qualities, I'm actually not a big fan of metal.